Spark-plug



M. S. WILLIAMS.

SPARK PLUG.

APPLICATION men JULY 5.19m.

Patented Apr. 20, 1920.

i STA'FES PATEN OFFICE;

MOWRY s. WILLIAMS, or SYRACUSR'NEW Yoax, Asszonon or ONE-HALF TO JOHN R.

CLAN CY, '01? SYRACUSE, NEW YORK.

SPARK-PLUG.

1 '0 all who/a it mag concern:

-Be it known that I, Mower S. VRLLIAMS, a citizen of the United States of America. and resident of Syracuse, in the county of Onondaga, in the State of New York, have invented new and useful Improvements in Spark-Plugs, of which the following, taken in connection with the accompanying drawin s', is a full, clear, and exact description. Ihis invention relates to certain improve ments in spark plugs as a part of an electric ignition system for internal combustion engines, the main object being to enable the same plug to be used under widely varying conditions as to sizes of the cylinders, degree ofelectl'ie energy in the ignition system and the amount; quality irhd nature of the fuel for the purpose of obtaining a maximum power and working efficiency of the engine. with a minimum quantity of fuel. This involves the"following structural features and advantagesz.

First,the adjustment of one of the terminals from the exterior while the engine is in operation to vary the spark gap according to the requirements under the varying conditions previously mentioned. and' also fol-cleaning purposes in bringing such terminal into wiping contact with the other terminal or bushing to remove carbon and other foreign matter which may accumulate thereon.

SecomL-the return-beinling of the adjustable terminal to prevent as far as pos sible the accumulation of oil or other foreign matter on the extremity thereof adjacent the spark gap.

'lhird,-the provision of a gas-tight joint between the. adjustable terminal and insulator in which it is mounted, and

Fourth,the construction of the insulator and other parts of the spark plug in such manner as to greatly increase its durability and security of adjustment.

Other objects and uses will be brought out in the following description.

In the drawings- Figure 1 is an elevation of a spark plug embodying the features of my invention.

Fig.2 is a longitudinal sectional view of the same.

Fig. 3 is a transverse sectional view taken on line 3-3, Fig. 1.

As illustrated, this spark plug comprises Specification of Letters Patent.

Patented Apr. 20; 1920.

Application filed July 5, 1916. Serial in. 107,538.

cclving the correspondingly tapered end of an insulating sleeve -6- which is held in place with its lower end against the shoulder lby an externally threaded follower engaging the internally threaded portion -2, as shown more clearly in Fig. 2. E

The insulating sleeve -6 is preferably circular in cross section throughout its length and extendssome distance above the upper end of the follower '7 when adusted for use. said mshlating sleeve being:

provided with a central lengthwise open:

ing -S- tberethrough from end to end, the upper end of which is threaded at 9- to receivea threaded electric conductor or spindle 10- which extends entirely through and beyond the opposite 'ends of said insulating sleeve.

The lower end of the spindle formed with a return-bend -11- terminating in a spark terminal 12- which extends axially of the plug from the return-l.)e .nd..-11-- toward and into close proximity to the adjacent lower end of the bushing --3-- to form a spark gap -13--.

The extremity of the spark terminal -12. therefore, lies directly under the annular shoulder 4- so that by turning the Spindle -l0-in one direction or the other in the sleeve -6, the extremity of the terminal 12 may be closer to or farther from the adjacent end of the bushing -3 to vary the spark gap -13 according to the requirements under varying conditions, such as the size of the cylinder. the degree of electric energy of the ignition circuit, or the amount or uality of the fuel, or this rotary and axial adjustment of the spindle -l0 may be used to bring the end of the terminal --1 into wiping contact with the adiacent end of the bushing -3- to clean the adjacent surfaces from accumulations of carbon or'other foreign matter.

made by ap lying a suitable tool the upper end tliereo while the engine is in operation.

One of the objects of the return-bend 11- at the junction of the spark terminal 12 withthe main body of the spindle 10 is to allow any oil or other foreign matter-which may tend to accumulate on said terminal to flow away from the sparking oint thereof toward the bend from which it maybe dropped into the cylinder, thereby reducing to a minimum one of the chief causes of ineflicient sparking.

When the s indle 10- 1s roperly adjusted, it is rmly locked to t e insulator -6 against relative movement by a suitable cap-nut 14- engaging the threaded portion of the spindle and upper end of the insulator.

ackin 15- of asbestos or equivalent insulatmg material is interposed between the adjacent ends of the cap 14- and insulator -6 and is referably screwed upon the threaded portion of the spindle to fit tightly thereonand thereby prevent leakage of gas throu h the opening in the insulator along the t reads of said spindle.

The upper end of the spindle may be wired in any well-known manner to the source of electric energy forming a art of the ignition system, such wire being eld in lace b a clamping nut 16- and washer -1?- engaging the upper threaded end of the. spindle which projects some distance above the clamping nut -l6 when the spark King is adjusted for use.

The bus ing -1 which constitutes a cooperative spark terminal may be screwed into the cylinder of the engine in the usual manner for spark plugs, and is grounded through the cylinder or other parts of the eggine or frame of the machine with suit a e connections to the opposite pole of the source of electric energy for completing the ignition circuit.

It is to be understood, however, that the team of connecting the spark plug to the source of electric energy forms no art of my invention and that 1 may be use with any suitable i 'tion circuit.

The lower tapering en ofthe insulating sleeve 6- is rovided with an annular groove or channel --18-- forming relatively narrow annuli -19 in the tapered bore -5- at opposite ends of the channel to secure a more perfect gas-tight joint,'the upper end of the upper annulus -19- forming a shoulder against which the lower end of the follower 7- abuts to firmly lock the insulator to the bushing with its lower end against the annular shoulder --4.

What I claim is: y r

A spark plug comprising a tubular metal bushing having itsinner end provided with an inturned annular flange, a one-piece tubular insulator having its inner end inserted in the bushing and terminatin against said flange and its outer end exten ing some distance beyond the outer end of the bushing and threaded internally, a threaded member screwing into the outer end of the bushing and engaging the insulator for holding its inner end against said flange, and an electric conductor extending entirely through and beyond the opposite ends of-the insulator and having its inner end returned outwardl toward said flange and its outer end threa ed and engaged with the internally threaded outer end of the insulator, whereby the turning of the spindle in reverse directions will cause its inner terminal end to rotate around said flange and at thesame time will vary the distance between the returned inner end of the conductor and the flange, the threaded engagement between particular manner the conductor and insulator serving to hold the conductor in its adjusted position.

In witness whereof I have hereunto set my hand this 23d day of June, 1916.

MOWRY S. WILLIAMS. Witnesses:

H. E. CHASE, Amos M. CANNON. 

